The Manx cat is believed to have originated hundreds of years ago on the Isle of Man, off the coast of England. Since many trade ships docked on the Isle, and all had ship cats, it is hard to tell just what the parent cat really was. Obviously, both longhair and shorthair were represented in the original mutation. Many longhairs were seen on the Island along with the shorthairs.

Records have been found on the Isle of Man that describe the cat as a mutation of the island’s domestic cats. It is believed that the island cats were involved, however, did some of the island cats come off the ships? We will never really know.

Geneticists believe that the Manx's taillessness occurred as the result of a spontaneous mutation. The breed proliferated because of the genetic nature of the tailless trait and centuries of inbreeding in an isolated island environment.

There are other, more fanciful, explanations for the Manx's lack of a tail.

According to one biblically inspired folktale, the Manx was the last of God's creatures to climb aboard the ark, barely making it before Noah slammed the door shut. A variation portrays Noah's dog as the culprit responsible for the loss of the cat's tail. In exasperation, the tailless cat fled the ark and swam from Ararat to the Isle of Man, where it found a home.

In another tale, Irish or Viking warriors stole kittens to use their tails as good luck charms. In order to save their kittens, the mother cats would bite off the tails of their young.